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Related papers: Turbulent density fluctuations in the solar wind

200 papers

We study scaling in fluctuations of the geomagnetic indices (AE, AU, and AL) that provide a measure of magnetospheric activity and of the epsilon parameter which is a measure of the solar wind driver. Generalized structure function (GSF)…

Space Physics · Physics 2015-06-26 B. Hnat , S. C. Chapman , G. Rowlands , N. W. Watkins , M. P. Freeman

We have measured the energy and dissipation of Alfvenic waves in the quiet Sun. A magnetic field was used to infer the location and orientation of the magnetic field lines along which the waves are expected to travel. The waves were…

Solar and Stellar Astrophysics · Physics 2015-06-22 Michael Hahn , Daniel Wolf Savin

Here we investigate the contribution of surface Alfven wave damping to the heating of the solar wind in minima conditions. These waves are present in regions of strong inhomogeneities in density or magnetic field (e. g., the border between…

Solar and Stellar Astrophysics · Physics 2015-05-14 R. M. Evans , M. Opher , V. Jatenco-Pereira , T. I. Gombosi

We study the acoustic properties of the solar chromosphere in the high-frequency regime using a time sequence of velocity measurements in the chromospheric Ca II 854.2 nm line taken with the Interferometric Bidimensional Spectrometer…

Astrophysics · Physics 2010-11-11 K. P. Reardon , F. Lepreti , V. Carbone , A. Vecchio

The origin and evolution of the 1/f power law observed in the energy spectrum of solar coronal and solar wind fluctuations at scales of around an hour is not entirely understood. Several existing theories aim at explaining it, involving…

Solar and Stellar Astrophysics · Physics 2022-10-26 Norbert Magyar , Tom Van Doorsselaere

Axford and McKenzie [1992] suggested that the energy released in impulsive reconnection events generates high frequency Alfv\'en waves. The kinetic equation for spectral energy density of waves is derived in the random phase approximation.…

Space Physics · Physics 2007-05-23 A. A. Galeev A. M. Sadovski

The spatial variation of physical quantities, such as the mass density, across solar atmospheric waveguides governs the timescales and spatial scales for wave damping and energy dissipation. The direct measurement of the spatial…

Solar and Stellar Astrophysics · Physics 2015-10-07 I. Arregui , R. Soler , A. Asensio Ramos

Turbulent magnetic field fluctuations observed in the solar wind often maintain a constant magnitude condition accompanied by spherically polarized velocity fluctuations; these signatures are characteristic of large-amplitude Alfv\'{e}n…

The interpretation of single-point spacecraft measurements of solar wind turbulence is complicated by the fact that the measurements are made in a frame of reference in relative motion with respect to the turbulent plasma. The Taylor…

Solar and Stellar Astrophysics · Physics 2015-06-19 G. G. Howes , K. G. Klein , J. M. TenBarge

Alfv\'enic fluctuations, as modelled by the non-linear interactions of Alfv\'en waves of various scales, are seen to dominate solar wind turbulence. However, there is also a non-negligible component of non-Alfv\'enic fluctuations. The…

Solar and Stellar Astrophysics · Physics 2024-02-15 Chaitanya Prasad Sishtla , Jens Pomoell , Norbert Magyar , Emilia Kilpua , Simon Good

We investigate the transition of the solar wind turbulent cascade from MHD to sub-ion range by means of a detail comparison between in situ observations and hybrid numerical simulations. In particular we focus on the properties of the…

Space Physics · Physics 2020-09-01 L. Matteini , L. Franci , O. Alexandrova , C. Lacombe , S. Landi , P. Hellinger , E. Papini , A. Verdini

Intermittent magnetohydrodynamical turbulence is most likely at work in the magnetized solar atmosphere. As a result, an array of scaling and multi-scaling image-processing techniques can be used to measure the expected self-organization of…

Astrophysics · Physics 2007-05-23 Manolis K. Georgoulis

We extend a two-component model for the evolution of fluctuations in the solar wind plasma so that it is fully three-dimensional (3D) and also coupled self-consistently to the large-scale magnetohydrodynamic (MHD) equations describing the…

Solar and Stellar Astrophysics · Physics 2016-12-14 Tobias Wiengarten , Sean Oughton , Eugene Engelbrecht , Horst Fichtner , Jens Kleimann , Klaus Scherer

We develop a 1D solar-wind model that includes separate energy equations for the electrons and protons, proton temperature anisotropy, collisional and collisionless heat flux, and an analytical treatment of low-frequency, reflection-driven,…

Solar and Stellar Astrophysics · Physics 2012-01-10 Benjamin D. G. Chandran , Timothy J. Dennis , Eliot Quataert , Stuart D. Bale

It is well established that the transverse MHD waves are ubiquitous in the solar corona. One of the possible mechanisms for heating both open (e.g. coronal holes) and closed (e.g. coronal loops) magnetic field regions of the solar corona is…

Solar and Stellar Astrophysics · Physics 2022-01-05 Samrat Sen , Vaibhav Pant

We develop a phenomenological model of strong imbalanced magnetohydrodynamic (MHD) turbulence that accounts for intermittency and the reflection of Alfven waves by spatial variations in the Alfven speed. Our model predicts the slopes of the…

Plasma Physics · Physics 2025-02-10 B. D. G. Chandran , N. Sioulas , S. Bale , T. Bowen , V. David , R. Meyrand , E. Yerger

We have measured the root-mean-square (RMS) amplitude of intensity fluctuations, $\Delta I$, in plume and interplume regions of a polar coronal hole. These intensity fluctuations correspond to density fluctuations. Using data from the…

Solar and Stellar Astrophysics · Physics 2018-06-27 Michael Hahn , Elke D'Huys , Daniel Wolf Savin

A statistical relationship between magnetic reconnection, current sheets and intermittent turbulence in the solar wind is reported for the first time using in-situ measurements from the Wind spacecraft at 1 AU. We identify intermittency as…

Space Physics · Physics 2015-06-19 K. T. Osman , W. H. Matthaeus , J. T. Gosling , A. Greco , S. Servidio , B. Hnat , S. C. Chapman , T. D. Phan

We present a measurement of the scale-dependent, three-dimensional structure of the magnetic field fluctuations in inertial range solar wind turbulence with respect to a local, physically motivated coordinate system. The Alfvenic…

Space Physics · Physics 2012-10-09 C. H. K. Chen , A. Mallet , A. A. Schekochihin , T. S. Horbury , R. T. Wicks , S. D. Bale

Magnetic field fluctuations measured in the heliosheath by the Voyager spacecraft are often characterized as compressible, as indicated by a strong fluctuating component parallel to the mean magnetic field. However, the interpretation of…

Space Physics · Physics 2024-08-01 L. -L. Zhao , G. P. Zank , M. Opher , B. Zieger , H. Li , V. Florinski , L. Adhikari , X. Zhu , M. Nakanotani